The numberingSystem accessor property of Intl.Locale instances returns the numeral system for this locale.

Description

A numeral system is a system for expressing numbers. For a list of supported numbering system types, see Intl.supportedValuesOf().

The numberingSystem property's value is set at construction time, either through the nu key of the locale identifier or through the numberingSystem option of the Intl.Locale() constructor. The latter takes priority if they are both present; and if neither is present, the property has value undefined.

The set accessor of numberingSystem is undefined. You cannot change this property directly.

Examples

Like other locale subtags, the numbering system type can be added to the Intl.Locale object via the locale string, or a configuration object argument to the constructor.

Adding a numbering system via the locale string

In the Unicode locale string spec, numberingSystem is an "extension subtag". These subtags add additional data about the locale, and are added to locale identifiers using the -u extension key. To add the numbering system type to the initial locale identifier string passed into the Intl.Locale() constructor, first add the -u extension key if it doesn't exist. Next, add the -nu extension to indicate that you are adding a numbering system. Finally, add the numbering system type.

const locale = new Intl.Locale("fr-Latn-FR-u-nu-mong");
console.log(locale.numberingSystem); // "mong"

Adding a numbering system via the configuration object argument

The Intl.Locale() constructor has an optional configuration object argument, which can contain any of several extension types, including numbering system types. Set the numberingSystem property of the configuration object to your desired numbering system type, and then pass it into the constructor.

const locale = new Intl.Locale("en-Latn-US", { numberingSystem: "latn" });
console.log(locale.numberingSystem); // "latn"

Specifications

Browser compatibility

See also

• Intl.Locale
• Intl.Locale.prototype.getNumberingSystems()
• Details on the standard Unicode numeral systems